Polyphase oscillator



Feb. 2, 1937. R. L. DAVIS 0 2,069,521

I POLYPHASE OSCILLATOR Filed June 15, 1935 D. C. supply I Source.

INVENTOR WITNESSES Patented Feb. 2, 1937 2 g 52 UNITED S'E'A'ifi FATENT OFFICE romrnsss OSCILLATOR Robert L. Davis, Grand Rapids, Mich, assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania Application June 15, 1935, Serial No. 26,791

4 Claims. (6!. 250-36) My invention relates broadly to the generation ners thereof, a Y or star connection of coils M, of polyphase high frequency currents and more the center point of which is grounded through a particularly to a system for the generation of source of power supply for the anodes R of the polyphase energy utilizing electronic tubes as the tubes 5, which anodes are connected to the cor- 5 generating means. ners of the delta arrangement of capacitors. In 5 One of the objects of my invention is to proeach branch of the delta arrangement, a suitvide an oscillation generator capable of developab e-gr d lea H is p ov d between the d and ing polyphase energy. the filament or cathode. Whereas in Fig. 1 the Another object of my invention is to provide anode E5 of each tube is connected to a condenser 10 suitable electron discharge device circuits capable 3 furthest removed from the grid connection, in 10 of the production of polyphase currents the arrangement of Fig. 2, the anode I5 is con- Additional objects of my invention will be nected to the coil 2| furthest from the grid conbrought out in the following description of the nection, the grids f e t es 5 in 2 being same. connected intermediate the condensers of each In the accompanying drawing, I have disclosed branch. The filaments H are connected in delta 15 two circuits embodying electron discharge d to conform with the other changes in the cir- Vices, each circuit being capable of carrying out Chit and are grounded as in thus p the objects of my invention, namely that of gens the plate Circuit for the tub crating high frequency polyphase currents. Each The p w r pp y source is shunted y a yof the circuits, as disclosed, is designed to genp ss o de ser Each of the above circuits 20 erate three-phase power, although it should be i capable of generating t -p as n y. t apparent that th cir it may b modified in being of particular interest to note that the exaccordance with the theory of polyphase trans- Citation for the grid of y One Of the tubes is former connections, to obtain the generation of not derived from the Plate Circuit of e same 5 high frequency energy at any number of phases, tube, but from the circuits of the other tubes. 25

Referring to Figure 1, the i uit comprises In other words, the generator does not comprise three inductors I connected in delta, and intermerely a combination f three s n le p ase scilconnecting the corners thereof I provide three iatols Connected to produce three-phase y, capacitors 3 connected in star connection, the but relies p n e act of t e Circuits center point of which is grounded. The electron of one tube with those of the Others to Obtain .30

discharge devices 5 embodied in the circuit are the desiredresultsconnected therein as follows. The grid 1 of each Thus in 1, for example, the grid of one tube is connected through a blocking condenser 9 tube derives its excitation from the plate to the midpoint of on of th delta connected cuits of the other two tubes and the same applies coils, a suitable grid leak ll being provided beto an the tubes of that circuit 35 tween the grid 1 and the fil t l3 which is In Fig. 2, we have a similar situation wherein connected or grounded to the center point of the the grid of any one tube derives its excitation t connected condensers The anode l5 of from the plate circuits of the other two tubes. each tube is not connected to either of the ad- Thus operation of the system requires that jacent capacitors of the Y connection, but is all the discharge devices be present in the cir- 40 connected to that condenser furthest from the Quit a the memo}, of one Wm St?!) t grid connection of the tube to the con Plate operation thereof mdicating that the excitation potential for the anodes may be applied to pram to at least one of the tubes has been suppressed.

tically any point in the delta connected coil ar- The energy output of the 08011-1 ator may 1 d therefrom through inductive or capacitive rangement although I have shown it as being 22$ ml or b direct con t connected to the midpoint of one of said coils. p g y necllon 0 any pot Ion of the circuit across which otential a The negative end of the plate potential supply p 5 re de veloped. bemg grounded closes the plate 011mm to the While I have disclosed two embodiments of my grounded portlon of the filament. invention, it should be apparent that various 50 n gt arrangement of the elements s changes may be suggested to those skilled in the sl y different from that Of l in that in art and I, therefore, desire that my protection be this circuit I have provided a delta arrangement not limited to the specific circuits and details of capacitors each branch containing a pair of disclosed except as may be necessitated by the condensers IT, IS, and interconnecting the corprior art and the appended claims. 55

I claim as my invention:

Y s V 1. A polyphase oscillator comprising a pluralof similar impedancesof one type connected in delta, a plurality of impedances of another type connected in star and arranged to interconnect the corners of said delta connection, and means for electrically connecting said control electrodes, each to a mid-point of the impedance in one of, said delta branches,.means for connecting said anodes, each to a corner of said delta arrangement, and means for connecting said cathodes in circuit with said anodes and control electrodes.

'2. A polyphase oscillator comprising a plurality of electron discharge devices each having a cathode, controlelectrode and anode, a plurality of capacitive impedancesconnected in de1ta,'a plurality of inductors connected in star, means for electrically interconnecting said'delta and star connections of impedances, means for electrically connecting said control electrodes, each to a 'midpoint of the capa'cit'ive impedance in one'of said delta branches, means for electrically connecting said anodes, each to a corner of said delta arrangement and means for connecting said cathodes in circuit with said anodes and control electrodes.

connecting said cathodes in circuit with 3. A polyphase oscillator comprising a plurality of electron discharge devices each having a rality of condensers connected in star between the cathode, control electrode and anode, a plurality V corners of said delta arrangement, means for elecv trically connecting'said control electrodes, each 1 to the mid-point of one of said inductive impedances, meansior electrically connecting said anodes each to a corner of said delta arrangement, and means for connecting said cathodes in'circuit with said anodes and oontrolelectrodes.

4. A polyphase oscillator comprising a plurality of electron discharge devices each having a cath-' ode, control "electrode and anode, a plurality of similar impedances of one type connected in delta,

a plurality of impedancesrof another type connected in star and arranged to'interconnect the corners of :said delta connection, means forcour pling said control electrodes, each to one of said impedances in the .delta'arrangement, means for coupling said anodes each to a corner of said:

delta arrangement, opposite to the connection of its associated control electrode, and means for said anodes and control electrodes.

ROBERT L. DAVIS. 

